442 BEARS CHAF< from living Mustelines by its comparatively long legs. In this genus as In several others there are two upper molars. Fam. 8. Ursidae. - This family is nearly universal in dis- tribution, and consists of but three genera, Ursits, Melursus, and Tfrsus has the palms and soles naked except in the Polar Bear, which needs a furry sole to walk with ease upon ice surfaces. The ears are fairly large, and the nose may or may not be traversed by a median groove.1 The molar formula2 is Pm £ M -§-. The brain Is naturally (because of the size of the animals of this genus) richly convoluted. The lobate kidneys have already been mentioned in denning this family (see p. 426). A very large number of species of- Bears have been described. :, .rlv-JjWC'Jr-^r^.' Fio. 224.—Himalayan Bear. Ursus tibetanus. x -^g-. But it Is the opinion of Mr. lydekker 3 and of others that many of these are really to be referred to the European Brown Bear; in this event the Grizzly of North America, the Isabelline Bear, the Syrian Bear, a Bear from Algeria, the Kamschatkan and Japanese Bears, besides the extinct Ursus fossilis of Pleistocene caves, are to be regarded as slight modifications of Ursus On the other hand, the great Cave Bear, 17. spelaeus, 1 Even apparently in the same species. 2 The number of premolars is reduced in the Polar Bear. 1 "The Blue Bear of Thibet," etc., froc. Zool Soc. 1897, p. 412.